JP2001278595A - Fall preventing device for working vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To move a boom within a safety range even if the operation of the boom is regulated by a fall preventing function. SOLUTION: This fall preventing device is formed of a working bench fitted to a tip of a turnable and telescopic boom, a boom operating device 10 for moving the working bench within a horizontal surface, and a control unit 30 for regulating the operation of the boom moving while riding over the preset safety area. Even if the operation of the boom is regulated, the control unit 30 allows the operation of the boom based on the boom operation when the operating signal input from the boom operating device 10 is the signal for moving the working bench within the safety range stored in a working range memory 32.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to
The present invention relates to a work vehicle having a boom device capable of freely extending and lowering, and more particularly to a fall prevention device for a work vehicle having such a boom device.

[0002]

2. Description of the Related Art A work vehicle having the above-mentioned boom device is, for example, an aerial work vehicle. The aerial work vehicle has a driving cabin and a boom device such as a cab-over type truck that can travel and is equipped with a boom device that can rotate, raise and lower, expand and contract, etc., and a work table on which the operator rides at the tip of the boom It is configured. The aerial work vehicle is used, for example, for aerial work at a construction site, maintenance / wiring work on a utility pole, and the like. It is configured so that it can be moved to a high place and work can be performed at a high place.

[0003] In a high-altitude work vehicle, when the boom is turned, raised and lowered, extended and retracted, and the work table is moved away from the vehicle, the position of the work table with respect to the vehicle body and the magnitude of the load acting on the work table. In response to this, a moment for causing the vehicle to fall, a so-called falling moment, acts. For this reason, the aerial work vehicle has a boom position detector that detects the position of the worktable, that is, a boom posture, and a load detector that detects a moment acting on the vehicle body from the boom,
An overturning device that stores a safety area set in advance based on the overturn limit and strength limit for the moment and that controls the operation of the boom when the workbench attempts to move beyond the safe area. Many are provided with a prevention device.

[0004]

However, in the conventional overturn prevention device, when the operation of the boom is restricted by the operation restriction control device, there is a possibility that the overturning moment may increase with respect to the subsequent boom operation. All boom operations are restricted, and there is a problem that some operation operations are not allowed even if the operation is within the safe area. For example, Figure 3 shows a state in which the aerial platforms viewed from above the vehicle when the operation of the boom is restricted by the horizontal regulation line of the vehicle side showing the distance x _0, in the drawing in this state when horizontally moving the work platform to H _1, H ₂ in the direction of the arrow to note, it is necessary to "pivot operate" and "extending action" boom 5. However, "it is extending action" of the boom 5 in the restricted state in the conventional anti-toppling device is not acceptable for the direction in which the overturning moment increases, actually even though the is a boom operating distance x ₀ is not changed not (or even a boom operation x ₀ is reduced), there is a problem that can not be horizontally moving the work platform in this direction.

FIG. 4 shows a state of the aerial work vehicle when the operation of the boom is regulated by a vertical regulation line on the side of the vehicle indicated by a distance X _{0 as} viewed from the rear of the vehicle. it is necessary to "Okoshiossha operation" and "extending action" boom 5 when to vertically move the work platform to V ₁ in the direction of the arrow made without departing. Further, it is necessary to "laid down operation" and "Chijimicho operating" the boom 5 when to vertically move the work platform in the direction of the arrow by appending V ₂ in FIG. However, in the conventional overturn prevention device, the “extension operation” and the “overturn operation” of the boom in the restricted state are not allowed because the overturning moment is in the increasing direction, and in reality, the boom operation in which the distance X ₀ does not change is performed. in spite (a boom operation is or X ₀ to shrink also), there is a problem that it is impossible to raise or lower the work platform in this direction.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and even when the operation of the boom is restricted by the overturn prevention device, the work table can be horizontally or vertically moved within the safety area. It is an object of the present invention to provide a work vehicle overturn prevention device with improved work efficiency.

[0007]

In order to achieve the above-mentioned object, a fall prevention device according to the present invention is provided on a boom capable of turning and extending and contracting at least at a movable vehicle, and a tip end of the boom. A workbench attached to the workbench, an operation control device for controlling the operation of the boom, and at least one of an operation of moving the workbench in a horizontal plane and an operation of moving the workbench in a vertical plane are possible and operate A boom operation device that outputs a signal corresponding to an operation to the control device to operate the boom, and stores a preset safety area and regulates the operation of the boom when the work platform attempts to move beyond the safety area. This is a device for preventing a work vehicle from overturning, comprising an operation restricting means. Then, the operation restricting means of the present invention (for example, the control unit 3 in the embodiment)
0) is that, even when the operation of the boom is restricted by the operation restricting means, the operation of the boom based on the operation for at least one of the horizontal movement and the vertical movement of the work table in the safety area is not changed. The work vehicle is configured to be allowed to fall to form a fall prevention device.

According to the overturn prevention device having the above-mentioned structure, even when the operation of the boom is restricted by the operation restricting means, the operation (boom operation) of moving the worktable in a horizontal plane within the safety area is not performed. The horizontal operation of the boom is performed based on the operation. Thus, for example, in the restricted state described above shown in FIG. 3, when the boom operation for horizontally moving the workbench H ₁ direction or H ₂ direction is performed,
Even operating with a "decompression operation" of the boom 5 is allowed, the distance x ₀ can be freely moved horizontally the platform within a range not increase (secure area). The preset safety area can be determined based on, for example, a fall limit, a strength limit, and the like, similarly to the safety area in the conventional fall prevention device.

[0009] Even when the operation of the boom is restricted by the operation restricting means, the operation (boom operation) of moving the work table in a vertical plane within the safety area is caused by raising and lowering the boom based on the operation. Directional operation is performed. Therefore, for example, in the above-described regulation state shown in FIG.
When horizontally moved to the boom operation the platform in _one direction or the V ₂ direction is made, even operating with the "extension operation" or "laid-down operation" of the boom 5 is allowed, the distance X ₀
The workbench can be freely moved up and down within a range (within the safety area) where does not increase.

Therefore, according to these overturn prevention devices,
It is possible to obtain a work area which cannot be moved because of the restriction with the conventional device, and it is possible to provide a fall prevention device that improves convenience and work efficiency in work while ensuring safety.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings. FIG. 2 shows an aerial work vehicle 1 as an example of a work vehicle having a fall prevention device according to the present invention. The aerial work vehicle 1 includes a driving cabin 2 and a turning motor 11 on a vehicle body 3 which is configured to be able to travel.
A turning table 4 is provided which is configured to be able to turn horizontally with respect to the vehicle body by the operation of. A freely configured boom 5 is pivotally connected by a pin 4a.

The boom 5 includes a base boom 5a pivotally connected to the swivel 4 and an intermediate boom 5b and a distal boom 5c.
The telescopic cylinder 13 arranged inside the boom 5 is configured to be freely expandable and contractable by the operation of the telescopic cylinder 13. At the tip of the tip boom 5c, there is provided a vertical post 6 which is always kept vertical regardless of the elevation angle of the boom 5 by the operation of a leveling cylinder (not shown). The worktable 8 is mounted so as to be freely horizontally swung (swinged).

A work platform 8 is provided with a boom operating device 10.
The work table 8 can be moved to an arbitrary altitude to perform a desired altitude operation by operating the boom 5 to raise and lower, rotate, extend and retract, swing the head, etc. ing. In addition, the vertical post 6 is provided with a winch 18 for facilitating lifting of a heavy object at a high place. It should be noted that when the boom 5 is turned or extended in this manner, or when a heavy object is lifted by the winch 18, the boom 5 resists the overturning moment acting in the direction in which the aerial work vehicle 1 is to be overturned. To stably support the car body 3,
Outrigger jacks 17 are arranged on the front, rear, left and right of the vehicle body 3.

When the operator operates the boom operating device 10 to move the worktable 8 to an arbitrary high place, the vehicle is mounted on the aerial work vehicle 1 by the overturning moment acting on the vehicle body 3 from the boom 5. A fall prevention device that regulates the operation of the boom 5 is mounted so as not to fall. FIG. 1 shows a configuration of a control device including the overturn prevention device, and will be described with reference to FIG. The control device has a control unit 30 to which operation signals and the like from the boom operation device 10 are input.

When the control unit 30 receives an operation signal from the boom operating device 10, the control unit 30 performs a turning operation of the swivel base 4 by the turning motor 11, an up / down operation of the boom 5 by the up / down cylinder 12, and a telescopic cylinder 13 in response to the operation signal.
, The swing operation of the worktable 8 by the swing motor 14 and the like. Note that, specifically,
Each operation is performed by a hydraulic cylinder, a hydraulic motor, or the like, and the control unit 30 outputs an operation control signal based on an operation signal to a hydraulic unit 40 provided on the vehicle body,
The operation of the electromagnetic control valve in this unit is controlled to control the operation of each hydraulic cylinder, hydraulic motor, and the like. The hydraulic cylinders and the like whose operation is controlled by the control unit 30 are collectively called an actuator.

The control unit 30 includes a boom position signal from the boom position detector 20 and a boom load detector 2.
5 is also input. The boom position detector 20 includes a turning angle detector 21 for detecting a turning angle of the boom 5 with respect to the vehicle body 3, and a boom 5 with respect to the vehicle body 3.
And an extension angle detector 22 for detecting the extension angle of the boom 5 and the like.
, The position of the tip (work table) of the boom 5 is detected and output to the control unit 30.

The boom load detector 25 includes the undulating cylinder 1
2 is provided on a pivot pin that pivotally pivots the up-and-down cylinder 12 between the tube side end and the swivel 4. This detector 25 detects an axial load acting in the direction of the expansion and contraction axis of the up-and-down cylinder 12, and the detected value is
Means the total moment acting on the vehicle body 3 around the foot pin from the boom 5 pivotably connected to the vehicle. This detection value is a value that changes depending on the undulation angle and the extension amount of the boom 5, but if the undulation angle and the extension amount of the boom 5 are known,
The overturning moment acting on the vehicle body can be geometrically calculated according to the boom posture.

The control unit 30 calculates the overturning moment acting on the vehicle body 3 in the arithmetic processing circuit 31 based on the load detection value input from the boom load detector 25 and the boom tip position input from the boom position detector 20. calculate. In the work range memory 32 in the control unit, a safe movable area of the work table (boom tip) with respect to the overturning moment acting on the vehicle body 3 is set and stored in advance as a function or a map-like regulation value. The control unit 30 compares the safety area corresponding to the calculated tipping moment with the boom tip position detected by the boom position detector 20.

When the tip of the boom is located within the safety area, an operation control signal corresponding to the operation signal from the boom operating device 10 is output to the hydraulic unit 40 to allow the operation of the boom 5 as it is. When an operation signal for moving the worktable 8 beyond the safe area is input, the operation control signal to the hydraulic unit 40 is regulated to operate the boom so that the worktable does not move beyond the safe area. Regulate.

When the boom operating device 10 is operated in a state where the operation of the boom is regulated as described above, the control unit 30 operates based on the operation signal input from the operating device 10 in the arithmetic processing circuit 31. The movement direction of the boom tip is calculated, and when it is determined that the movement direction is within the safe area, an operation control signal corresponding to the operation signal is output to the hydraulic unit 40 and the operation of the boom based on the boom operation is directly performed. Allow.

[0021] For example, already in regulating the state shown in FIG. 3, and the direction indicated by H ₁ or H ₂ in the figure, the boom operation for horizontally moving the platform to the vehicle body (the direction in which x ₀ is reduced) than this Is performed, even if the operation involves the extension operation of the boom 5, this operation is permitted, and the work table can be freely moved within the safety area. Alternatively, in the regulation state shown in FIG. 4, a boom operation for vertically moving the worktable in the direction indicated by V ₁ or V ₂ in the figure or in the vehicle body side (the direction in which X ₀ is reduced) is performed. Occasionally, an operation involving an extension operation or a fall operation of the boom 5 is allowed, and the work table can be freely moved within the safety area.

On the other hand, when it is determined from the operation signal input to the control unit 30 that the moving direction of the boom tip calculated by the arithmetic processing circuit 31 is a direction of moving beyond the safety area, the hydraulic unit 40 To regulate the operation of the boom 5.

For example, in the regulation state shown in FIG.
₁ or or when the outside of the vehicle body than in the direction indicated with H ₂ boom operation for moving the work platform towards (x ₀ is a direction to expand) is performed, V ₁ or V ₂ in regulating the state shown in FIG. 4
When the boom operation of moving the work platform towards is performed outside of the vehicle body than the direction (direction X ₀ is enlarged) indicated by regulates the operation of the boom 5.

Therefore, according to the overturn prevention device configured as described above, the overturn prevention device having the same overturning safety as that of the conventional overturn prevention device can be controlled and moved while being within the safety area in the conventional device. A work area that could not be obtained can be obtained, and a fall prevention device that improves convenience and work efficiency in work while ensuring safety can be obtained.

The boom operating device 10 may be any operating device capable of operating the boom by outputting an operation signal corresponding to the operation of the boom. For example, a single operating lever can be used for horizontal movement or vertical movement. A so-called joystick type HV control operating device that can be operated, or an independent operating type operating device provided with three operating levers corresponding to each of the turning, undulating and telescopic actuators, based on a computer program or the like. Or the like, which outputs an operation signal.

In the above description, the horizontal movement and the vertical movement are separately described. However, when the horizontal movement and the vertical movement are simultaneously operated, the control device which can move the work table in the combined direction thereof is not provided. By judging whether or not the combined direction is within the safe area and allowing the boom operation when the combined direction is within the safe area, the same boom operation as in the above embodiment can be performed.

[0027]

As described above, according to the present invention, a boom capable of turning and expanding and contracting at least on a runnable vehicle, a worktable attached to the tip of the boom, and the worktable are moved in a horizontal plane. A boom operation device that can operate at least one of an operation and an operation of moving in a vertical plane and outputs a signal corresponding to the operation to the boom operation control device to operate the boom, and a safety area set and stored in advance. An operation restricting device for restricting the operation of the boom that attempts to move over the work vehicle, wherein the operation restricting device has a workbench within a safe area even when the operation of the boom is restricted. The operation of the boom based on the operation of performing at least one of horizontal movement and vertical movement Constitute the stop apparatus. Therefore, even a boom operation in which the overturning moment increases in a single operation is permitted for a boom operation that moves within a safe area in a combined operation, and therefore, it was not possible to move with a conventional restriction. It is possible to provide a fall prevention device in which a work area is expanded and safety is ensured, and work convenience and work efficiency are improved.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of a control device including a fall prevention device according to the present invention.

FIG. 2 is a perspective view of an aerial work vehicle having the overturn prevention device according to the present invention.

FIG. 3 is an explanatory diagram for explaining an operation of a conventional fall prevention device and a fall prevention device according to the present invention.

FIG. 4 is an explanatory diagram for explaining the operation of the conventional fall prevention device and the fall prevention device according to the present invention.

[Explanation of symbols]

Reference Signs List 1 aerial work vehicle (working vehicle) 3 body 5 boom (5a base end boom, 5b intermediate boom, 5
c Tip boom) 8 Work table 10 Boom operating device 30 Control unit (operation control device, operation restriction means)

Continuation of the front page (72) Inventor Takao Kanazawa 1012, Yamashita, Yamato, Ryoke, Ageo-shi, Saitama F-term (reference) 3F333 AA08 FA09 FA34 FA40

Claims (1)

[Claims] 1. A boom disposed on a vehicle that can travel and capable of at least turning and expanding and contracting, a work table attached to a tip of the boom, and an operation control device that controls operation of the boom. And at least one of an operation of moving the work table in a horizontal plane and an operation of moving the work table in a vertical plane, and outputs a signal corresponding to the operation to the operation control device to output the boom. Boom operating device for operating the boom, and operation restricting means for storing a preset safety area and restricting the operation of the boom when the workbench attempts to move beyond the safety area. A fall prevention device for a work vehicle, wherein the operation restricting means horizontally moves the work table within the safety area even when the operation of the boom is restricted by the operation restricting means. And vertical as acceptable fall prevention device for a working vehicle, characterized in that the operation of the boom based on the operation to the operation for at least one of the mobile.